#include <stdio.h>
#include <string.h>

int main() {
  int i1 = 1;
  int s1 = sizeof(i1);
  printf("i1=%d, sizeof=%d\n", i1, s1);
  char* str = "test str\n";
  int charSizeOf = sizeof(str);
  printf("str sizeof=%c\n", *str);

  int nums[] = {1,12,3};
  int* header = nums;
  header++;
  printf("header: %d\n", *header);

  char c1 = 'c';
  char c2[] = "string";
  int len = strlen(c2);
  char *c3;
  // strcpy(c3, c2);
  
  printf("c3: %d\n", len);

  int a = 123;
  int aa = a % 10;
  char cc = aa + '0';
  printf("mod %c, %d\n", cc, cc);



  return 0;
}